Soap vs Detergent: What's the Difference?

The short answer is: soap is natural and detergent isn’t. But there’s more to it than that.

Soap is created by mixing fats and oils with an alkali or base. This method has been around for hundreds of years--remember the soft soap Ma used in the Little House books? It was created with ashes (that contain lye, a base) with animal fats.

Since soap is natural, it is biodegradable and less harmful to the environment than detergents. However, the minerals in water react with soap and can turn clothes gray and leave a film or residue.

Detergents are made by combining chemicals in a slurry mixer. The mixture heats up as a result of chemical reactions, and then it’s dried and powdered to form the final product. On average, there are about ten steps between the original raw materials and the final detergent.

Because detergents don’t react as much with the minerals in water, though, they’re the best choice for laundry (but not babies).

How can I tell the difference?
It’s confusing because most detergents are camouflaged as soaps. Manufacturers use the terms “facial bar” and “body cleansing bar” to keep us guessing. What’s a girl to do? Read the label. Look for chemicals like sodium lauryl sulfate or cocomidopropyl betaine, and then run the other way. True soaps have ingredients like oils, saponified oils, or glycerin.

What should I buy?
As always, you need to do your homework and make your own decisions. We use castile soap (bars or liquid from Mountain Rose Herbs) to wash ourselves and for housecleaning. For laundry, we make our own or choose natural detergents without synthetic fragrances and dyes.

Soap and detergent are used on our skin, our clothes, and in our homes. Immediately after use, they go down the drain and into our environment. Doesn’t it make sense to use the least toxic products we can find?

This article was shared on Small Footprint Friday.